In this guide you’ll learn how to downgrade iOS 4.0.2 to iOS 4.0.1 / 4.0 on iPhone 4, 3GS, 3G and iPod Touch 3G, 2G. Instruction on how to downgrade iPhone, iPod Touch iOS 4.0.2 to 4.0.1/4.0 firmware can be found below.

In this guide we’ll use TinyUmbrella to downgrade iPhone / iPod Touch firmware. There’s no need to edit any Hosts file that is required in other guides found all over the cloud. We are going to setup downgrade server the TinyUmbrella way: with a single click.

Step 3 – Start TSS Server

Hit the Display SHSH button to confirm that downloaded SHSH blobs has been cached by TinyUmbrella for 4.0.1 or 4.0. (If you already have them in your PC, drag and drop the SHSH blobs in the TinyUmbrella window then hit the display SHSH blobs button to confirm).

I run tinyumbrella but it says “TSS server will not work”. It says “NOT running as administrator OR your hosts file is not editable – Cannot listen on port 80”. I am the administrator on this computer so what is the problem?

if you have a 3g, you can just easily downgrade it to 4.0.1 in restoring with it.just download iOS 4.0.1 firmware for iphone 3g.
if you have an iphone 3gs ,you can downgrade your iphone if you have saved shsh blobs for 4.0.1. just do the instruction above given by iphone heat,,.. tested by me

I have now a 3GS with release 4.0.1 (8A306) jailbreaked and unlocked. The Device is SHSHs saved @ cydia. (This device has SHSHs on file for iphone os ios 4.0.1)

My question is that I will get the new iphone 4 within the next two weeks and i’m sure (of course), they put 4.0.2 🙁 on it. Is it possible to go back then or not even when I have a save @ cydia? Or do i have to do a lokal save from the old device via TinyUmbrella ?
greets from zurich

Hi for all. Well. My girlfriend bought the iphone 4 and the first thing she did was connect to itunes and upgrade to 4.0.2 and therefore never knew you had to save the SHSH. The iphone is not locked, I can access the area of work but have no idea how to install cydia. Can anybody
help?

I bought the iphone 3GS and the first thing I did was connect to itunes and upgrade to 4.0.2 it works but i never knew you had to save the SHSH. The iphone is not locked, I can access the area of work but have no idea how to install cydia.please help me.

Ive just got an activated iphone 4 with 4.0.2 installed
Is there anyway I can downgrade to 4.0.1 and unlock it to use with any carrier.
The steps above don’t mention the iphone 4 listed, only other models. Can anyone confirm? thanks.

Bought new i-phone 4 last week whilst on holiday in the states . Had an AT&T card in so was able to activate . As
don’t have SHSH saved for this phone only for my 3GS . So
should i upgrade to 4.2 from 4.0.2 and wait for unlock and
jailbreak ?

Regarding steps 4 & 5, i got two situations that i did not quite understand. For step number 4, my error message said “3194”, not “1015”, “1013”, or “1011”. On step 5, trying to exit recovery mode, i went into tinyumbrella and my button for “Kick device out of recovery” isnt even applicable to press. My mc-it2g is version 4.0.2 right now, and when i downloaded the shsh file for 4.0 i wasnt exactly sure if that was what i was supposed to do. Anyways, here is a link to a photo of both the incidents I was talking about: http://s233.photobucket.com/albums/ee273/elephant3232/?action=view&current=untitled.jpg
If you know anything about what i can do to jailbreak my ipod, please, anything will help!

Ive retried multiple times-at least three times-and gotten the same “3194” error and it continues to say my software version is still 4.0.2. And where exactly is Recboot once i finally get the right error message? Sorry, im new to this.